近年來，資訊嵌入或資訊隱藏的技術愈來愈多，其目的是讓我們能夠藏入額外的資料在原本的檔案裡。而這些檔案的類型有很多種，例如圖檔、影片檔和音訊檔案。資料嵌入可以用於保護著作權和秘密通訊等領域上。
這些隱藏的技術，大體上可以分成二種類型：一種是在空間域(spatial domain)，而另一種則是在頻率域(Frequency domain)中嵌入資料。在空間域裡，主要的原理就是小幅度地改變原始影像的像素值，使得人眼不易察覺，進而達到隱藏資料的目的。在頻率域中，則是利用了人眼對於高頻訊號不易感知的原理，所以我們可以對高頻訊號加以改變，仍使肉眼不易看出改變之處，而達到資料隱藏的目標。
現今大部份的資料隱藏方法，大多都著墨於彩色和灰階色域之上，而鮮少有方法是針對純粹黑白兩色的影像。這主要是因為彩色和灰階的影像中，每一像素值的範圍很大(0~255)，若我們輕微更改其像素值，人眼不易發覺；然而在黑白的影像之中，改變少部份的像素值，人眼卻對此影像很敏感，因此黑白影像的資料隱藏方法很少有人提及。
本篇論文即是要提出一套在黑白影像中嵌入資料的方法。此方法是先對整張影像作一次前處理，以避免模稜兩可(ambiguity)的問題發生。再來就是根據定義好的參數，找出可以藏入資料的樣版(pattern)。而藏入的方法則是看此樣本的黑像素的個數，若為偶數，則代表藏入”0”；若為奇數，則代表藏入”1”。此方法對於文字文件、中國毛筆字、以及手寫簽名字等黑白影像表現特別好，而且在取出資料時，不必事先知道原本的檔案大小以及範圍，只要確實地把整個藏入後的部份都包含進來即可進行解碼的動作，實在是一項方便又強大的優點。

A simple data hiding technique for binary images is proposed. It is a “pattern” based method instead of block based like most of others. The embedding rules are as follows: If the number of black pixels in a pattern is even, it implies that this pattern embeds a “0”. If the number of black pixels in a pattern is odd, it implies that this pattern embeds a “1”. It adds one black pixel at the left or right hand side of the pattern to fit the embedding rules. We use a weighting mechanism to determine which side we can add well. Before embedding, we apply a pre-processing to the binary image to avoid the ambiguous problem. The pre-processing may increase capacity of the image. This method is suit for binary images, especially good for text document, Chinese calligraphy, and hand-writings. We can extract the data from the binary image without prior knowledge of the original size of the image.

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